Unicentric castleman's disease located in the lower extremity: a case report

<p>Abstract</p> <p>Background</p> <p>Castleman's disease is a rare form of localized lymph node hyperplasia of uncertain etiology. Although the mediastinum is the most common site of involvement, rare cases occurring in lymph node bearing tissue of other localization have been reported, including only a few intramuscular cases. Unicentric and multicentric Castleman's disease are being distinguished, the latter harboring an unfavorable prognosis.</p> <p>Case Presentation</p> <p>Here, we present a case of unicentric Castleman's disease in a 37-year-old woman without associated neoplastic, autoimmune or infectious diseases. The lesion was located in the femoral region of the right lower extremity and surgically resected after radiographic workup and excisional biopsy examinations. The tumor comprised lymphoid tissue with numerous germinal centers with central fibrosis, onion-skinning and rich interfollicular vascularization. CD23-positive follicular dendritic cells were detected in the germinal centers and numerous CD138-positive plasma cells in interfollicular areas. The diagnosis of mixed cellularity type Castleman's disease was established and the patient recovered well.</p> <p>Conclusions</p> <p>In conclusion, the differential diagnosis of Castleman's disease should be considered when evaluating a sharply demarcated, hypervascularized lymphatic tumor located in the extremities. However, the developmental etiology of Castleman's disease remains to be further examined.</p

Cartilage defect repair in horses : Current strategies and recent developments in regenerative medicine of the equine joint with emphasis on the surgical approach

Chondral and osteochondral lesions due to injury or other pathology are highly prevalent conditions in horses (and humans) and commonly result in the development of osteoarthritis and progression of joint deterioration. Regenerative medicine of articular cartilage is an emerging clinical treatment option for patients with articular cartilage injury or disease. Functional articular cartilage restoration, however, remains a major challenge, but the field is progressing rapidly and there is an increasing body of supportive clinical and scientific evidence. This review gives an overview of the established and emerging surgical techniques employed for cartilage repair in horses. Through a growing insight in surgical cartilage repair possibilities, surgeons might be more stimulated to explore novel techniques in a clinical setting

Nanofracturing: a new technique for bone marrow stimulation in equine cartilage repair

Microfracture is the current standard in treatment of focal full-thickness cartilage lesions in horses, but clinical outcome may vary. Nanofracture is a novel technique that uses a commercially developed device to yield smaller diameter perforations with deeper penetration into the subchondral bone. Experimentally, in rabbits and sheep, nanofracture has been shown to result in superior repair compared to microfracture. The objective was to study the feasibility and preliminary outcome of nanofracture using a commercial device for treatment of cartilage defects in horses. Nanofracture was tested ex vivo in n=2 cadaveric equine stifle joints and in vivo in n=8 horses with experimental partial thickness cartilage defects in the medial femoral trochlear ridge. These were treated with an experimental biomaterial or nanofracture, and repair tissue was studied macroscopically (ICRS-I score) and microscopically (histological ICRS-II score and micro-CT) after 7 months. Both in cadaveric equine stifle joints and in vivo, the nanofracture device could readily be applied and allowed easy penetration of the subchondral bone. Repair tissue after 7 months was graded ‘near-normal’ macroscopically, while histologically, the abundant repair tissue proved mainly fibrocartilaginous in nature. Micro-CT revealed near-full restoration of mid-lesion cartilage layer thickness but altered subchondral bone microarchitecture. The in vivo study did not include a control group treated with conventional microfracture for comparison. To our knowledge, this is the first report on bone marrow stimulation using nanofracture as a potential method to enhance chondral defect repair in horses. In the in vivo study, no clinical adverse effects were observed, and promising good defect filling with fibrocartilaginous tissue was seen 7 months after treatment.La microfractura es el estándar actual en el tratamiento de lesiones focales de cartílago de grosor completo en caballos, pero el resultado clínico puede variar. La nanofractura es una técnica novedosa que utiliza un dispositivo desarrollado comercialmente para producir perforaciones de menor diámetro con una penetración más profunda en el hueso subcondral. Experimentalmente, en conejos y ovejas, se ha demostrado que la nanofractura da lugar a una reparación superior en comparación con la microfractura. El objetivo era estudiar la viabilidad y el resultado preliminar de la nanofractura utilizando un dispositivo comercial para el tratamiento de defectos del cartílago en caballos. La nanofractura se probó ex vivo en n=2 articulaciones de la ahogada cadavérica equina e in vivo en n=8 caballos con defectos de cartílago de espesor parcial experimental en la cresta troclear del fémur medial. Estos fueron tratados con un biomaterial experimental o nanofractura, y el tejido de reparación fue estudiado macroscópicamente (puntuación ICRS-I) y microscópicamente (puntuación histológica ICRS-II y micro-TC) después de 7 meses. Tanto en las articulaciones de la ahogada equina cadavérica como in vivo, el dispositivo de nanofractura podía aplicarse fácilmente y permitía una fácil penetración del hueso ubcondral. El tejido de reparación después de 7 meses fue calificado acroscópicamente como 'casi normal', mientras que histológicamente, el abundante tejido de reparación demostró ser principalmente de naturaleza fibrocartilaginosa. La micro-TC reveló una restauración casi completa del grosor de la capa de cartílago de la lesión media, pero alteró la microarquitectura del hueso subcondral. El estudio in vivo no incluyó un grupo de control tratado con microfractura convencional para la comparación. Hasta donde sabemos, este es el primer informe sobre la estimulación de la médula ósea usando la nanofractura como un método potencial para mejorar la reparación de defectos condrales en caballos. En el estudio in vivo, no se observaron efectos clínicos adversos, y se vio un buen relleno del defecto con tejido fibrocartilaginoso 7 meses después del tratamiento.Escuela de Medicina Veterinari

Orthotopic bone regeneration within 3D printed bioceramic scaffolds with region-dependent porosity gradients in an equine model

The clinical translation of three-dimensionally printed bioceramic scaffolds with tailored architectures holds great promise toward the regeneration of bone to heal critical-size defects. Herein, the long-term in vivo performance of printed hydrogel-ceramic composites made of methacrylatedoligocaprolactone-poloxamer and low-temperature self-setting calciumphosphates is assessed in a large animal model. Scaffolds printed with different internal architectures, displaying either a designed porosity gradient or a constant pore distribution, are implanted in equine tuber coxae critical size defects. Bone ingrowth is challenged and facilitated only from one direction via encasing the bioceramic in a polycaprolactone shell. After 7 months, total new bone volume and scaffold degradation are significantly greater in structures with constant porosity. Interestingly, gradient scaffolds show lower extent of remodeling and regeneration even in areas having the same porosity as the constant scaffolds. Low regeneration in distal regions from the interface with native bone impairs ossification in proximal regions of the construct, suggesting that anisotropic architectures modulate the cross-talk between distant cells within critical-size defects. The study provides key information on how engineered architectural patterns impact osteoregeneration in vivo, and also indicates the equine tuber coxae as promising orthotopic model for studying materials stimulating bone formation.La traducción clínica de andamios biocerámicos impresos tridimensionalmente con arquitecturas adaptadas es muy prometedora para la regeneración de hueso para curar defectos de tamaño crítico. En este caso, el rendimiento in vivo a largo plazo de los compuestos impresos de cerámica de hidrogel hechos de metacrilato-oligocaprolactona-poloxámero y fosfatos de calcio de baja temperatura que se fijan por sí mismos se evalúa en un modelo de animal grande. Se implantan andamios impresos con diferentes arquitecturas internas, que muestran un gradiente de porosidad diseñado o una distribución de poros constante, en los defectos de tamaño crítico del tubérculo coxae equino. El crecimiento óseo se desafía y se facilita sólo desde una dirección mediante el encapsulamiento de la biocerámica en una cáscara de policaprolactona. Después de 7 meses, el volumen total de hueso nuevo y la degradación del andamiaje son significativamente mayores en estructuras con porosidad constante. Curiosamente, los andamios con pendiente muestran un menor grado de remodelación y regeneración incluso en zonas que tienen la misma porosidad que los andamios constantes. La baja regeneración en las regiones distales de la interfaz con el hueso nativo perjudica la osificación en las regiones proximales de la construcción, lo que sugiere que las arquitecturas anisotrópicas modulan la diafonía entre las células distantes dentro de los defectos de tamaño crítico. El estudio proporciona información clave sobre la forma en que las pautas arquitectónicas de ingeniería repercuten en la osteoregeneración in vivo, y también indica que el tubérculo equino coxae es un modelo ortotópico prometedor para estudiar los materiales que estimulan la formación ósea.Universidad Nacional, Costa RicaEscuela de Medicina Veterinari

Deep digital flexor tendon injury a the level of the proximal phalanx in frontlimbs with tendon sheath distension characterized by standing low-field magnetic resonance imaging in horses : 13 cases (2015-2021)

Objective: To describe the MRI findings for 13 horses with deep digital flexor tendon (DDFT) injury at the proximal phalanx where the tendon goes from ovoid to bibbed in frontlimbs with tendon sheath distension. In addition, the prognosis of this lesion was assessed. Design: Retrospective case series. Animals: Thirteen client-owned horses. Procedures: Medical records were reviewed, and data were collected regarding signalment, history, MRI findings, and outcomes of horses. Findings of MRI were recorded and whether the case was confirmed with tenoscopy. Results: A diagnosis of DDFT injury at the junction between ovoid and bibbed portions at the level of the proximal phalanx was established in 13/20 (65%) horses that underwent MRI examination of the frontlimb digital flexor tendon sheath. Return to previous level of work was poor in this subset of horses with only three of 13 (23%) horses returning to previous level of work and one horse still in rehabilitation. Conclusions and Clinical Relevance: Standing low-field MRI represents a potentially useful diagnostic tool to evaluate digital flexor tendon sheath distension especially when evaluating the DDFT at the proximal phalanx where the tendon progresses from ovoid to bibbed. Prognosis of lesions of the DDFT at the proximal phalanx appears less favorable than previously reported causes of tendon sheath distension

Orthotopic Bone Regeneration within 3D Printed Bioceramic Scaffolds with Region-Dependent Porosity Gradients in an Equine Model

The clinical translation of three-dimensionally printed bioceramic scaffolds with tailored architectures holds great promise toward the regeneration of bone to heal critical-size defects. Herein, the long-term in vivo performance of printed hydrogel-ceramic composites made of methacrylated-oligocaprolactone-poloxamer and low-temperature self-setting calcium-phosphates is assessed in a large animal model. Scaffolds printed with different internal architectures, displaying either a designed porosity gradient or a constant pore distribution, are implanted in equine tuber coxae critical size defects. Bone ingrowth is challenged and facilitated only from one direction via encasing the bioceramic in a polycaprolactone shell. After 7 months, total new bone volume and scaffold degradation are significantly greater in structures with constant porosity. Interestingly, gradient scaffolds show lower extent of remodeling and regeneration even in areas having the same porosity as the constant scaffolds. Low regeneration in distal regions from the interface with native bone impairs ossification in proximal regions of the construct, suggesting that anisotropic architectures modulate the cross-talk between distant cells within critical-size defects. The study provides key information on how engineered architectural patterns impact osteoregeneration in vivo, and also indicates the equine tuber coxae as promising orthotopic model for studying materials stimulating bone formation

Long-Term in Vivo Performance of Low-Temperature 3D-Printed Bioceramics in an Equine Model

Bone has great self-healing capacity, but above a certain critical size, bone defects will not heal spontaneously, requiring intervention to achieve full healing. Among the synthetic calcium phosphate (CaP) bone replacement materials, brushite (CaHPO4·2H2O)-based materials are of particular interest because of their degree of solubility and the related high potential to promote bone regeneration after dissolution. They can be produced tailor-made using modern three-dimensional (3D) printing technology. Although this type of implant has been widely tested in vitro, there are only limited in vivo data and less so in a relevant large animal model. In this study, material properties of a 3D-printed brushite-based scaffold are characterized, after which the material is tested by in vivo orthotopic implantation in the equine tuber coxae for 6 months. The implantation procedure was easy to perform and was well tolerated by the animals, which showed no detectable signs of discomfort. In vitro tests showed that compressive strength along the vertical axis of densely printed material was around 13 MPa, which was reduced to approximately 8 MPa in the cylindrical porous implant. In vivo, approximately 40% of the visible volume of the implants was degraded after 6 months and replaced by bone, showing the capacity to stimulate new bone formation. Histologically, ample bone ingrowth was observed. In contrast, empty defects were filled with fibrous tissue only, confirming the material’s osteoconductive capacity. It is concluded that this study provides proof that the 3D-printed brushite implants were able to promote new bone growth after 6 months’ implantation in a large animal model and that the new equine tuber coxae bone model that was used is a promising tool for bone regeneration studies

Long-term in vivo performance of low-temperature 3D-printed bioceramics in an equine model

Bone has great self-healing capacity, but above a certain critical size, bone defects will not heal spontaneously, requiring intervention to achieve full healing. Among the synthetic calcium phosphate (CaP) bone replacement materials, brushite (CaHPO4·2H2O)-based materials are of particular interest because of their degree of solubility and the related high potential to promote bone regeneration after dissolution. They can be produced tailor-made using modern three-dimensional (3D) printing technology. Although this type of implant has been widely tested in vitro, there are only limited in vivo data and less so in a relevant large animal model. In this study, material properties of a 3D-printed brushite-based scaffold are characterized, after which the material is tested by in vivo orthotopic implantation in the equine tuber coxae for 6 months. The implantation procedure was easy to perform and was well tolerated by the animals, which showed no detectable signs of discomfort. In vitro tests showed that compressive strength along the vertical axis of densely printed material was around 13 MPa, which was reduced to approximately 8 MPa in the cylindrical porous implant. In vivo, approximately 40% of the visible volume of the implants was degraded after 6 months and replaced by bone, showing the capacity to stimulate new bone formation. Histologically, ample bone ingrowth was observed. In contrast, empty defects were filled with fibrous tissue only, confirming the material’s osteoconductive capacity. It is concluded that this study provides proof that the 3D-printed brushite implants were able to promote new bone growth after 6 months’ implantation in a large animal model and that the new equine tuber coxae bone model that was used is a promising tool for bone regeneration studies.El hueso tiene una gran capacidad de autocuración, pero por encima de un cierto tamaño crítico, los defectos óseos no se curan espontáneamente, por lo que es necesario intervenir para lograr una curación completa. Entre los materiales sintéticos de sustitución ósea de fosfato de calcio (CaP), los materiales a base de brusquitos (CaHPO4-2H2O) son de particular interés por su grado de solubilidad y el elevado potencial que presentan para promover la regeneración ósea después de la disolución. Pueden producirse a medida utilizando la moderna tecnología de impresión tridimensional (3D). Aunque este tipo de implante ha sido ampliamente probado in vitro, sólo hay datos limitados in vivo y menos en un modelo relevante de animal grande. En este estudio se caracterizan las propiedades del material de un andamiaje tridimensional impreso a base de grafito, tras lo cual el material se prueba mediante la implantación ortotópica in vivo en el tubérculo equino coxae durante 6 meses. El procedimiento de implantación fue fácil de realizar y fue bien tolerado por los animales, que no mostraron ningún signo detectable de molestia. Las pruebas in vitro demostraron que la resistencia a la compresión a lo largo del eje vertical del material densamente impreso era de alrededor de 13 MPa, que se redujo a aproximadamente 8 MPa en el implante cilíndrico poroso. En vivo, aproximadamente el 40% del volumen visible de los implantes se degradó después de 6 meses y fue reemplazado por hueso, lo que demuestra la capacidad de estimular la formación de nuevo hueso. Histológicamente, se observó un amplio crecimiento del hueso. En cambio, los defectos vacíos se llenaron sólo con tejido fibroso, confirmando la capacidad osteoconductiva del material. Se llega a la conclusión de que este estudio aporta pruebas de que los implantes de grafito tridimensional fueron capaces de promover el crecimiento de nuevo hueso después de 6 meses de implantación en un modelo de animal grande y que el nuevo modelo de hueso de tubérculo equino coxae que se utilizó es una herramienta prometedora para los estudios de regeneración ósea.Universidad Nacional, Costa RicaEscuela de Medicina Veterinari